Heat control



Sept. 3, 1946. E, Q SQN 2,407,095

HEAT CONTROL Filed April 16, 1945 Elmer Olson INVENTOR.

ATTORNEY.

Patented Sept. 3, i946 HEAT CONTROL Elmer Olson, Ferndale, Mich., assignor to George M. Holley and Earl Holley Application April 16, 1945, Serial No. 588,629

1 Claim.

The object of this invention is to prevent the following difficulty arising: After an engine has been driven for some time with the throttle wide open, the driver stops the engine and seeks refreshment. At the end of 20 minutes, he restarts the engine. During this intervening 20 minutes, the heat has risen through the flange into the throttle and beyond the throttle to the float chamber, and the gasoline in the float chamber has boiled and discharged to the inlet manifold, which is now full of gasoline Vapor. This gasoline vapor makes a non-explosive fog, the mixture being too rich to fire. By waiting about ten minutes and then cranking the engine slowly with the throttle wide open, the engine is restarted without much difficulty. To avoid this trouble, asbestos gaskets are provided between the inlet manifold and the carburetor, and a large number of trick solutions have been tried and a few have been used. However, no satisfactory solution to the problem has yet been presented. One objection to asbestos gaskets is that a certain amount of heat around the throttle is desirable in cold weather. It is not practical to have asbestos gaskets in summer and metal gaskets in winter.

I have discovered that if I give the heat something to do besides boiling the gasoline, it will be diverted and absorbed, and very little of it will reach the float chamber.

Figure 1 shows a cross-sectional elevation on plane l-l of Figure 2.

Figure 2 is a cross-sectional plan view of Figure 1.

- Figure 3 is a cross-sectional elevation similar to Figure 1.

In the figures, II] is the air entrance, II is the choke valve therein, [2 is the nozzl discharging into a restricted portion of the air entrance, I3 is a fuel nozzle and I4 is a low-speed fuel passage, which discharged adjacent to and on the downstream side of the upstream lip of the butterfly throttle I5. I6 is the flange of the outlet from the carburetor, I1 is the heated inlet manifold flange to which the flange I6 is bolted by bolts 20, I8 is a shell embracing the flange I6, I9 is a hollow space within the shell l8, filled with a metal, for example, it may conform to the alloy known as 3879 consisting of bismuth 38.4, cadmium 15.4, lead 30.8 and tin 15.4, which has a melting point of l59.8 F. (See page 1328, K. R. Van Horns Metals Handbook, American Society of Metals, Cleveland, Ohio, 1939; also, see page 432, circular C447, National Bureau of Standards, Mechanical Properties of Metals and Alloys.)

This metal has appreciable latent heat. Therefore, before the temperature of the flange I6 can exceed 59.8 F., the metal contained in [9 must be melted. For the same reason, once havhaving melted, it will stay warm for a longer period of time, and, therefore, not only is the heat prevented from interfering with restarti but this heat actually is useful in facilitating restarting without moving the choke valve ll into the position in which it is shown; in other words, without getting an abnormally rich mixture when restarting.

Figure 3 shows a slight modification of Figure 1, The element 23 is separate from the flange 2i of the carburetor and is placed above the inlet manifold 25, which has an inlet passage 26 separated from the exhaust gases contained in the manifold 25. A groove 24 in the element '23 is filled with this metal alloy #3879. Two bolts 22 are used to connect the carburetor flange 2 l with the inlet manifold 25.

In place of alloy #3879, alloy #3880 may be used, consisting of bismuth 50, cadmium 6.2, lead 34.5 and tin 9.3, which has a melting point of 170.6" F.

What I claim is:

A hollow flange interposed between an exhaustheated inlet manifold and a carburetor, filled with a fuseable metal having a melting point below F.

ELMER OLSON. 

